Embodiments presented herein relate to microelectronic device structures and, more particularly, to three-dimensional (3D) microelectronic integrated circuit (IC) chip structures including increased thermal dissipation capability.
Microelectromechanical systems (MEMS) are miniaturized devices, such as microswitches that may range in size from less than 1 micron to about 1 mm or more. 3D integrated circuits in general, include two or more layers of electronic components in a stacked configuration that are integrated both vertically and horizontally. These devices generally require a controlled environment to operate for a long period of time. Dissipation of heat is a major issue in any high-power electronics or electrical application, and extremely important in high-powered microelectromechanical systems or MEMS devices. Through substrate vias, referred to as TSVs, are utilized as conductors in the stack of chips, such as memory chips, providing amongst other functions, a heat path between the chips. Additional means for dissipating heat may be integrated.
Most MEMS devices are interconnected using wirebonding. However, in high power MEMS applications, wirebonding can lead to severe limitations in the performance of the device. Limitations associated with wirebonding are related to the following factors, including, but not limited to, current handling capability of the wires and an insufficient thermal path that may particularly impact handling of short current surges. In other instances, MEMS device may be interconnected using ribbon bonding with similar limitations in the performance of the device.
In addition to performance degradation due to inadequate thermal dissipation, the introduction of contaminants such as moisture, particulates or gas into the environment surrounding the device can cause sticking, contamination, or interference of the metal contacts, leading to device failure.
Accordingly, an improved microelectronic chip structure including increased thermal management, such as improved heat dissipation paths, resulting in a more reliable high-performance device with increased current carrying capabilities may be desired. In addition, it may provide protection from contaminants to an active device.